diff --git a/pkgs/desktops/xfce4-14/libxfce4ui/default.nix b/pkgs/desktops/xfce4-14/libxfce4ui/default.nix
index de34e2b6af5..2ea6d195d6f 100644
--- a/pkgs/desktops/xfce4-14/libxfce4ui/default.nix
+++ b/pkgs/desktops/xfce4-14/libxfce4ui/default.nix
@@ -1,5 +1,5 @@
 { lib, mkXfceDerivation, gobject-introspection, gtk2, gtk3, libICE, libSM
-, libstartup_notification ? null, libxfce4util, xfconf }:
+, libstartup_notification, libxfce4util, xfconf }:
 
 mkXfceDerivation rec {
   category = "xfce";
diff --git a/pkgs/desktops/xfce4-14/orage/default.nix b/pkgs/desktops/xfce4-14/orage/default.nix
index 3c8395a4908..8c453aa96a2 100644
--- a/pkgs/desktops/xfce4-14/orage/default.nix
+++ b/pkgs/desktops/xfce4-14/orage/default.nix
@@ -1,5 +1,5 @@
 { lib, fetchpatch, mkXfceDerivation, dbus-glib, gtk2, libical, libnotify, tzdata
-, popt, libxfce4ui ? null, xfce4-panel ? null, withPanelPlugin ? true }:
+, popt, libxfce4ui, xfce4-panel, withPanelPlugin ? true }:
 
 assert withPanelPlugin -> libxfce4ui != null && xfce4-panel != null;
 
diff --git a/pkgs/desktops/xfce4-14/parole/default.nix b/pkgs/desktops/xfce4-14/parole/default.nix
index 77e614b493b..578be8329b0 100644
--- a/pkgs/desktops/xfce4-14/parole/default.nix
+++ b/pkgs/desktops/xfce4-14/parole/default.nix
@@ -1,7 +1,7 @@
 { mkXfceDerivation, dbus, dbus-glib
-, gst-plugins-bad ? null, gst-plugins-base, gst-plugins-good
-, gst-plugins-ugly ? null, gtk3, libnotify, libxfce4ui, libxfce4util
-, taglib ? null, xfconf }:
+, gst-plugins-bad, gst-plugins-base, gst-plugins-good
+, gst-plugins-ugly, gtk3, libnotify, libxfce4ui, libxfce4util
+, taglib, xfconf }:
 
 # Doesn't seem to find H.264 codec even though built with gst-plugins-bad.
 
diff --git a/pkgs/desktops/xfce4-14/thunar/default.nix b/pkgs/desktops/xfce4-14/thunar/default.nix
index 9497952eafd..ed0be442023 100644
--- a/pkgs/desktops/xfce4-14/thunar/default.nix
+++ b/pkgs/desktops/xfce4-14/thunar/default.nix
@@ -1,5 +1,5 @@
-{ mkXfceDerivation, docbook_xsl, exo, gdk-pixbuf, gtk3, libgudev ? null
-, libnotify ? null, libX11, libxfce4ui, libxfce4util, libxslt, xfconf, gobject-introspection, gvfs }:
+{ mkXfceDerivation, docbook_xsl, exo, gdk-pixbuf, gtk3, libgudev
+, libnotify, libX11, libxfce4ui, libxfce4util, libxslt, xfconf, gobject-introspection, gvfs }:
 
 mkXfceDerivation rec {
   category = "xfce";
diff --git a/pkgs/desktops/xfce4-14/xfce4-settings/default.nix b/pkgs/desktops/xfce4-14/xfce4-settings/default.nix
index ba512f05e83..21aaef5fd08 100644
--- a/pkgs/desktops/xfce4-14/xfce4-settings/default.nix
+++ b/pkgs/desktops/xfce4-14/xfce4-settings/default.nix
@@ -1,6 +1,6 @@
 { mkXfceDerivation, automakeAddFlags, exo, garcon, gtk3, glib
-, libnotify ? null, libxfce4ui, libxfce4util, libxklavier ? null
-, upower ? null, xfconf, xf86inputlibinput ? null }:
+, libnotify, libxfce4ui, libxfce4util, libxklavier
+, upower, xfconf, xf86inputlibinput }:
 
 mkXfceDerivation rec {
   category = "xfce";
diff --git a/pkgs/desktops/xfce4-14/xfce4-volumed-pulse/default.nix b/pkgs/desktops/xfce4-14/xfce4-volumed-pulse/default.nix
index 626451c70d6..b1405910021 100644
--- a/pkgs/desktops/xfce4-14/xfce4-volumed-pulse/default.nix
+++ b/pkgs/desktops/xfce4-14/xfce4-volumed-pulse/default.nix
@@ -1,4 +1,4 @@
-{ lib, mkXfceDerivation, gtk3, libnotify ? null, libpulseaudio, keybinder3, xfconf }:
+{ lib, mkXfceDerivation, gtk3, libnotify, libpulseaudio, keybinder3, xfconf }:
 
 mkXfceDerivation rec {
   category = "apps";